This invention pertains to a method for holding a cathode-ray tube in a fixed position during processing, such as a faceplate mechanical grind operation.
In manufacturing a cathode-ray tube, an antiglare surface is put on the faceplate of the tube by a dry mechanical grind operation in order to reduce the gloss on the faceplate surface. It is important that the tube be held in a fixed plane during this operation so that a uniform surface finish is put on the faceplate. Presently, a fiberglass mold is fitted to the funnel of the cathode-ray tube, and this "saddle" fixture supports the tube during the mechanical grind operation.
During this processing, the cathode-ray tube has a tendency to shift and jump out of the saddle fixture, which presents a safety hazard in the factory. Whenever the tube shifts, the saddle fixture removes a conductive coating from scuffed areas where the external surface of the funnel contacts the saddle fixture. This requires the completed tube to be repainted with conductive paint. Also, since the saddle fixture does not secure the tube in a fixed plane, there is a tendency not to get a completely uniform surface finish on the faceplate. The present apparatus and method overcome the above disadvantages by holding the cathode-ray tube in a fixed position during such processing.